Papers

We present $\texttt{SPINE}$ and $\texttt{SPINEX}$, a pair of analytical emulators developed to predict the nonlinear power spectrum based on its linear counterpart and several essential cosmological parameters within the range of $0.01\;h\;\mathrm{Mpc}^{-1} <k< 2\;h\;\mathrm{Mpc}^{-1} $. The primary difference between the two models is their parameterisation. Our methodology is grounded in the mapping originally proposed by Peacock and Dodds (1996). Both models are defined by clear mathematical expressions derived from symbolic regression, a machine learning technique that utilises genetic programming to identify analytical equations that accurately represent the underlying data. This approach provides a more interpretable and efficient alternative to conventional numerical methods that should also exhibit superior extrapolation behaviour beyond the training range. The emulators have been trained on the $\Lambda$CDM Quijote Latin Hypercube simulations. We provide fits for both emulators across three distinct scenarios: cosmologies within 20$\sigma$ of the Planck-2018 observations, a designated fiducial cosmology, and a broader range of cosmologies sampled from the Quijote simulations. Our findings indicate that $\texttt{SPINE}$ and $\texttt{SPINEX}$ maintain an accuracy of better than 5% in the majority of cases. These emulators provide a rapid alternative to numerical methods, and future initiatives will focus on developing expressions that incorporate galaxy bias and redshift-space distortions. This advancement aims to enhance the modelling of redshift space power spectra across multiple redshifts, enabling their application in large-scale cosmological surveys.

We study the stellar mass-size relation of satellite galaxies in the COLIBRE suite of cosmological hydrodynamical simulations. Satellites deviate from the relation that holds for centrals galaxies, where at the high mass end, $\log (M_*/{\rm M}_\odot) > 10.5$, sizes (defined as the 3D half-mass radius $r_{\rm h,*}$) increase systematically with mass ($r_{\rm h,*} \propto M_*^{0.5}$), whereas at lower masses, $8 < \log(M_*/{\rm M}_\odot) < 10.5$, the relation flattens and galaxy size becomes, on average, almost independent of mass ($r_{\rm h,*} \approx 3$ kpc). At $z=0$, dwarf satellites (defined as those with $8 < \log(M_*/{\rm M}_\odot) < 9$) are systematically larger than centrals of similar $M_*$. This trend reverses for bright satellites ($9 < \log(M_*/{\rm M}_\odot) < 10.5$), which are typically smaller than centrals of similar mass. We trace these trends to evolutionary processes affecting satellites after infall into the haloes of more massive hosts. At infall, dwarf satellites are typically gas-rich, dark matter-dominated systems with relatively large baryon-induced cores. These satellites quench rapidly after losing their gas to ram pressure, which prompts an immediate impulsive expansion due to the shallowing central potential, followed by secular expansion as their cored dark matter haloes are gradually stripped by tides. In contrast, the inner regions of bright satellites are baryon-dominated and resilient to tides. Centrally concentrated star formation increases their stellar mass, leading to smaller sizes and higher stellar metallicities (by $\approx 0.2$ dex) than those of centrals of similar mass. These distinct satellite evolutionary pathways lead to identifiable features in the mass-size-metallicity relations that may be compared with observations.

Extreme and intermediate mass-ratio inspirals in a dense dark-matter distribution have the effects of the dark matter imprinted on the orbital dynamics of and the emitted gravitational waves from these systems. Prior work has shown that space-based gravitational-wave detectors can measure the dark-matter-induced effects on the gravitational waves, which would give evidence for the presence of dark matter around the massive black hole. In this earlier work, the dark matter has been assumed to have only gravitational interactions (namely, no dark-matter self-annihilation or interactions between dark matter and ordinary baryonic or leptonic matter). In this article, we investigate the gravitational-wave effects of introducing such interactions of dark matter with itself or with ordinary matter in binaries with a neutron-star secondary. We consider broad classes of dark-matter models that change the distribution of dark matter (spikes or annihilation plateaus) and which permit accretion onto the secondary, as well as an increasing or static mass of the neutron star during the inspiral (in addition to the purely gravitational effect of dynamical friction). We find distinctive gravitational-wave signatures of these interactions and of self-annihilation, which in some of the scenarios could be sufficiently large for space-based detectors to distinguish them using gravitational-wave observations of these systems.

The threshold theorem states that quantum computations can be made reliable below a physical error threshold, at the cost of additional physical qubits and circuit depth. Recent work has reduced these space and time overheads to polylogarithmic or nearly logarithmic scalings, but whether the cumulative spacetime overhead can be constant has remained unclear. Here, we show that even for the simplest task of preserving quantum information in a quantum memory, under an optimistic noise model and allowing general adaptive protocols, there is an unavoidable logarithmic contribution to the cumulative spacetime overhead. This additional cost can nevertheless be shared among many logical qubits, so sufficiently wide computations, including standard implementations of Shor's algorithm, may still achieve constant relative overhead. We further give a positive-rate CSS code construction that attains the memory bound, identify sufficient conditions under which the same scaling extends from quantum memory to fault-tolerant circuit implementations, and derive circuit-size bounds for subsystem spacetime codes. Our work establishes fundamental limits on the resources required for quantum fault tolerance.

We present results of a systematic validation of the \lalsuite{} timing model for continuous gravitational waves against \pint{}, a modern high-accuracy pulsar-timing package. An accurate timing model is essential for tracking the signal phase, and hence for detecting and accurately characterizing continuous gravitational waves. In order to quantify the impact of timing inaccuracies, we derive and validate the leading-order relation $\mu \approx (2\pi f)^2\stddtau^2$, where $\mu$ is the fractional loss of signal power, $f$ is the signal frequency, and $\stddtau^2$ is the variance of the timing errors. We then compare the solar-system and binary components of the \lalsuite{} timing model against the corresponding models in \pint{}. With the original \lalsuite{} Einstein-delay implementation, the total disagreement is dominated by that component and has $\stddtau\simeq\SI{2.3}{\micro\second}$ (corresponding to $\mu\simeq\SI{0.02}{\percent}$ at $f=\SI{1000}{\hertz}$). With the newer Einstein-delay implementation, the total disagreement (over one year) drops to $\stddtau\lesssim\SI{31}{\nano\second}$ (or $\mu\lesssim\num{4e-8}$ at $f=\SI{1000}{\hertz}$) and is dominated by the observatory contribution to the \Romer{} delay, owing to the approximate Earth-rotation model used by \lalsuite{}. We additionally test binary delays using orbital parameters from \num{474} catalogued binary pulsars and verify the self-consistency of the \lalsuite{} source-time derivatives. Finally, we derive and discuss the \lalsuite{} Shapiro delay for signals passing through the solar interior, a case only relevant to gravitational waves.

Periodically driven quantum systems provide a powerful route to engineer novel states of matter by controlling their effective Hamiltonians through external fields. However, most treatments are usually simplified by considering the high-frequency limit, and do not account for the processes taking place in the transient regime during the onset of the drive. In this work, we introduce a time and momentum resolved tunneling spectroscopy protocol to probe the instantaneous energy spectrum of Floquet-driven systems beyond the high-frequency regime, capturing both emergent effects and non-adiabatic phenomena without requiring explicit reconstruction of the full time-dependent Green's function. We benchmark the method on driven non-interacting fermionic models, and then generalize the approach to strongly correlated systems with the aid of time-dependent density matrix renormalization group techniques. We also provide a microscopic description to the emergence of in-gap states under resonant driving, and briefly explore its finite temperature analog.

The quantum geometric tensor - the Berry curvature together with the quantum metric - now underlies a long list of observables, from the anomalous Hall effect to the superfluid weight of a flat band. We ask which of these observables actually require quantum mechanics. To answer this question, we study a purely classical system: a point particle carrying a classical magnetic moment $\boldsymbol{\ell}$ that precesses in a momentum-dependent magnetic field $\mathbf{B}(\mathbf{p})$. Within Hamiltonian classical mechanics, the component of $\boldsymbol{\ell}$ along the field reproduces the Berry-curvature phenomena, while its precessing transverse component reproduces the quantum-metric phenomena. The particle acquires a position spread whose second moment is the metric, an orbital magnetic moment, and - most strikingly - an inertial mass generated by a position-dependent force, and with it a nonzero Drude weight in a system that is nominally dispersionless.

The Koopman-von Neumann framework has been proposed to design quantum algorithms for non-linear dynamics. It maps a non-linear ordinary differential equation to a linear partial differential equation (PDE) governing a probability amplitude. Previous works represents this amplitude in the Hermite-function basis, equivalently as a bosonic state, and truncates the total Hermite degree to obtain a representation over $\Theta(m\log N)$ qubits, where $N$ is the number of variables and $m$ the truncation order. We extend this approach to a broader class of linear PDEs whose differential operators have a structured polynomial form. We prove convergence of the truncation for both time-dependent dynamics and gapped ground-state problems under explicit regularity and stability assumptions. We then introduce a qubit encoding that supports efficient block encodings of the truncated operators. Finally, we apply the framework to Bayesian inverse problems with Gaussian priors and observation noise, reducing posterior-state preparation to the preparation of a structured Hamiltonian's ground state.

The ${\cal M}$-theory dual of thermal QCD-like theories constructed in arXiv:1306.4339, 2004.07259 involves, as shown in arXiv:2211.13186, a closed $G_2$-structure seven-fold $\mathcal{M}_7$ supporting Contact 3-Structures (C3S) that induce a “transverse” $SU(3)$-structure. We prove that this induced structure belongs to the symplectic nearly half-flat (S(nearly)HF) class: $d\omega_\Phi=0$ exactly, while $d\Omega_+$ is suppressed as $\mathcal{O}(e^{-N^{1/3}/\mathcal{O}(1)})$ in the infrared "MQGP limit", leaving $W_\Phi^{SU(3)}=W_2^-$ as the sole non-vanishing Chiossi–Salamon torsion class and completing the $G$-structure classification of the MQGP dual initiated in arXiv:1507.02692,2004.07259, 2211.13186. As a physical application, Kaluza–Klein reduction of the eleven-dimensional Hodge dual of the differential of the $G_2$-structure positive three-form on $\mathcal{M}_7$, organised through the $G_2$/S(nearly)HF torsion data, yields a radial “magnetic field” $\mathcal{B}_{\rm KK}(r)$ whose squared norm factorises exactly into external and internal factors. $\mathcal{B}_{\rm KK}(r)$ satisfies a Bessel-type ODE with a regular singular point at the horizon; normalisability and infrared regularity select $J_2$, with harmonicity of the aforementioned internal factor recovered from the large-$N$ suppression. $\mathcal{B}_{\rm KK}$ is related to the magnetic field of the type~IIA flavour $D6$-branes via a non-linear power law, furnishing a top-down holographic mechanism for generating weak magnetic fields in finite-temperature string theory.

Quantum anomalies strongly constrain the possible behavior of many-body systems. A prime example is the Lieb-Schultz-Mattis (LSM) theorem, which relates UV symmetry and filling constraints to IR features of the energy spectrum and ground-state structure. Here, we ask how LSM constraints shape dynamical signatures and temporal correlations in open quantum systems. Using a spacetime duality, we show that the Liouvillian of a $d$-dimensional repeated quantum channel with a mixed anomaly between strong $S$ and weak $G$ symmetry can be mapped to a $(d{+}1)$-dimensional mixed-state symmetry-protected topological (mSPT) phase. Under this correspondence, the initial and steady states of the channel are identified with boundary states of the higher-dimensional mSPT in the presence of bulk projection. We further introduce the twisted Renyi-$N$ correlator (TRNC) as a probe of temporal correlations in the channel and demonstrate that it is dual to the mSPT strange correlator, providing a direct bulk-boundary route to diagnose long-range temporal order implied by the LSM anomaly. Finally, we identify the Liouvillian singular spectrum, rather than the Liouvillian spectrum itself, as a more fundamental diagnostic of quantum anomalies, and show that it is dual to the operator entanglement spectrum of the mSPT.

The non-Abelian statistics of Majorana zero modes has inspired numerous proposals for their detection and manipulation in topological superconductors. Implementations based on magnetic adatoms deposited on superconductors draw particular attention due to their capabilities for precise atomic manipulation and the control over disorder. Here, we propose a scheme for detecting changes in the ground state parity of a topologically non-trivial adatom system by passing supercurrent through their low-energy modes. We unravel characteristic discontinuities in the critical current driven by zero-energy level crossings. We apply these findings to a setup where the Majorana coupling is mediated by a single control magnetic adatom hosting a Yu-Shiba-Rusinov state, and test the robustness of our results against finite temperatures and different tunneling regimes. Our findings introduce a non-invasive approach for reading out and controlling the ground state parity of Majorana states in Shiba-Majorana hybrid systems.

How does the Bose or Fermi statistics of microscopic particles survive when confinement binds them into emergent bosonic composites? We address this question in the strong-coupling limit of a $2+1$D $\mathbb{Z}_2$ lattice gauge theory, where charges are confined into tightly bound pairs that can be described by an effective dimer model. We find that the statistics of the underlying matter is encoded entirely in a single local hopping phase $\varphi$ -$0$ for bosons, $\pi$ for fermions. Treating $\varphi$ as a continuous parameter that interpolates between the two, we map the ground-state phase diagram with the help of tensor-network methods. The angle $\varphi$ itself drives a transition between a dimer-superfluid and a dimer-charge density wave state, while the magnetic coupling binds neighboring dimers into resonating pairs, in competition with the inter-dimer repulsion. We identify a novel gapped phase in which dimer pairs crystallize into an ordered pattern of resonating plaquettes. Finally, we propose a quench protocol under which identical dimer configurations evolve in markedly different ways depending on the statistics of their constituents. This provides a dynamical probe of the internal structure of dimers, and allows to detect ordered phases through real-time signatures, within reach of simulators that natively realize bosonic degrees of freedom.

Galactic conformity is usually interpreted as a signature of assembly-biased galaxy occupation. We investigate whether compensated combinations of galaxy correlations can recover the linear matter correlation-function shape on scales where ordinary clustering becomes nonlinear. Using colour-selected DESI BGS and SDSS MGS samples, we measure conformity and compensated statistics in projection and redshift space, and compare them with MTNG, FLAMINGO, and MDPL2-SAG simulations. We find that the DESI conformity monopole, projected conformity, and compensated correlations follow the linear matter shape to substantially smaller separations than ordinary colour-selected clustering. The agreement is clearest for dense DESI samples with central-primary selection, although the dependence on primary selection varies with scale and statistic. Projected conformity resembles the unprojected linear matter correlation function more closely than its projected counterpart, consistent with an effective response concentrated at small line-of-sight separations. The conformity quadrupole is strongly suppressed, as expected from cancellation of the leading Kaiser terms. SDSS shows similar but noisier behaviour, while simulations reproduce the main trends with model-dependent amplitudes. These results suggest that compensated statistics can suppress nonlinear clustering contributions while retaining linear matter information, although residual nonlinear effects require calibration before precision cosmological applications. (Abridged)

The ratio of $s$-process to $\alpha$-element enrichment ($[s/\alpha]$) has been proposed as a “chemical clock,” or a means to estimate stellar ages. However, the age–$[s/\alpha]$ relation varies with metallicity and location in the Galaxy, and the observed trends are not well predicted by galactic chemical evolution models. We quantify the age–[Ce/Mg] correlation across the Galactic disk in roughly 100,000 red giant stars observed with APOGEE in the SDSS-V Milky Way Mapper survey. We find that the slope of the correlation varies significantly with metallicity and guiding radius in the chemical thin disk. The trend is steepest in the outer disk and below Solar metallicity, while the most metal-rich stars and those in the inner disk show no correlation with age. In contrast, [Ce/Mg] patterns in the chemical thick disk are consistent across the Galaxy. Halo stars have higher [Ce/Mg] than the chemical thick disk, suggesting that asymptotic giant branch (AGB) enrichment is important even at low metallicity. Overall, patterns in [Ce/Mg] trace both the local star formation history and AGB nucleosynthesis. The complex interplay between [Ce/Mg], age, metallicity, and Galactic position means that [Ce/Mg] (and by extension $[s/\alpha]$) is not a universal chemical clock.

We show that a magnet can remain perfectly collinear while its quantum vacuum circulates. In a centrosymmetric altermagnet, a symmetry-allowed locally staggered Dzyaloshinskii-Moriya coupling imprints a gauge-irremovable vortex-antivortex pair into the anomalous magnon pair correlations at high-symmetry points in momentum space. In real space, these hidden vortices produce an antiferrochiral array of equilibrium spin currents circulating oppositely around neighboring plaquettes. Gauge-irremovable frustration therefore survives despite classical collinearity: it exists entirely in the quantum correlations. Our results show that complex pairing, gauge-invariant fluxes, and equilibrium loop currents - structures encountered across electronic flux phases, spin liquids, and frustrated quantum magnets - can be encoded in the squeezed vacuum of a collinear magnet.

IceCube has recently detected a diffuse population of high-energy neutrinos arising from the Milky Way. We use this high-significance detection to place new limits on dark matter (DM) annihilation to neutrinos with two complementary approaches. The first method uses the background-subtracted Galactic longitude distribution of shower events to place a conservative bound on the DM annihilation cross section that does not rely on any assumed Galactic cosmic ray emission model; the resulting limits on the velocity-averaged annihilation cross section improve upon existing bounds by factors of a few. The second method uses the template-dependent neutrino energy spectra from the Inner Galaxy, inferred under different Galactic cosmic ray emission models. This complementary approach shows that the inferred Galactic neutrino intensities are already sensitive to DM contributions near the thermal-relic benchmark for a range of TeV-scale DM masses, though this comparison is more model-dependent. Our results demonstrate that measurements of diffuse Galactic neutrino emission can be used as a powerful probe of DM annihilation into neutrinos. Future observations with IceCube-Gen2 and KM3NeT will substantially extend this sensitivity, potentially allowing a decisive test of the thermal freeze-out mechanism with Galactic neutrino observations.

The combination of gravitational collapse and an accelerating expansion of the Universe drive an increasing fraction of volume toward becoming low-density voids across cosmic time. These regions present a unique environment due to their low density, which leads to them behaving similarly to "pocket universes" with modified cosmological parameters. Since the formation and evolution of galaxies is strongly tied to the environment, we aim to discern how voids alter halos and galaxies compared to the general population in the universe. We use the hydrodynamical cosmological simulation suite Magneticum Pathfinder and introduce a set of void halo mass functions (VHMFs), which trace the halo population as a function of void-centric distance. We find galactic halos in voids to be overall less massive than in the general simulation volume. This discrepancy between void and field halos evolves with time as the voids grow more underdense, while the populations are still very similar at cosmic dawn. Expanding on this, we evaluate whether specific properties of the voids affect the VHMFs. We find the only relevant parameter for the void halo population to be the core density, a measure of the strength of underdensity. To assess the impact of the density environment on the evolution of galaxies, we investigate whether there are any distinctions between void and field galaxies with regard to stellar properties. We compute the stellar-mass function, halo mass-stellar mass relation, as well as the star-forming main sequence using the same void-centric shells. Although voids contain overall less stellar mass, the distribution of galaxies along the stellar mass-halo mass follows that of other regions. This implies that SF proceeded "conventionally" in void regions, in agreement with more recent observations.

Accelerator-based experiments at the intensity frontier, in which a high-energy beam impinges on a nuclear target, serve as powerful probes of the light dark matter paradigm. Such experiments require precise modeling of the target nucleus for reliable signal predictions. We present the application of a many-body ab initio method to calculate light dark matter mediator production signal rates at electron fixed-target experiments, using chiral effective field theory interactions. Considering both elastic and quasi elastic scattering, we compute cross sections using a Monte Carlo event generator implementation informed by ab initio nuclear elastic form factors and spectral functions for three representative nuclei, $^{20}$Ne, $^{34}$Si, and $^{56}$Fe, at varying electron beam energies. We compare our results to a commonly used phenomenological parameterization, finding an increased signal yield by up to two orders of magnitude with our quasi elastic treatment and an agreement for lighter mediators.

In recent years, significant progress has been made in the development of automated tools that match the parameters of new physics models and the appropriate low-energy Effective Field Theories. This work introduces an extensible, hybrid tool, OperatorToC++, that combines the strengths of Mathematica and C++ to facilitate the next steps beyond the matching. OperatorToC++ efficiently tackles the complexities within the analytical matched expressions such as intricate loop-functions and lengthy sums and products involving tensor objects. It then translates and bundles the results into C++ classes and functions which provide a convenient platform for further numerical analyses. Finally, it offers the possibility of calling the compiled Wilson coefficient methods as Python functions, thus enabling to link them with the vast Python library ecosystem for High Energy Physics workflows.

We study overlaps of late-time states in semiclassical de Sitter quantum gravity. In a family of deformations of de Sitter JT gravity, we compute the no-boundary wavefunction to one-loop and derive the ultralocal late-time measure. The one-universe contribution to the norm is exactly eight times the sphere amplitude, so the pairing used by the Lorentzian measure differs from that implicit in Euclidean gravity. After summing over disconnected final universes, the no-boundary norm exponentiates the one-universe result, giving $\langle \!\langle \text{HH}|\text{HH}\rangle\!\rangle \approx \exp(4Z_{\rm sphere})$ rather than the sum over closed geometries, $Z_{\rm closed}\approx \exp(Z_{\rm sphere})$. We also review an analogous mismatch in Einstein gravity with positive cosmological constant, where the late-time no-boundary norm vanishes at one-loop, differing from the Euclidean sphere amplitude. We discuss the implications for cutting and gluing in perturbative gravity, and features that arise when extending this construction to sums over topologies.

Magic-angle helical trilayer graphene—three graphene layers sequentially twisted in the same direction by $\sim1.8^\circ$—relaxes into a mosaic of domains that, at zero field, carry opposite valley-resolved Chern numbers, with boundaries hosting a network of gapless conducting modes. Charge transport through this network depends sensitively on how the modes connect and scatter, making well-quantized transport unlikely. Contrary to this expectation, we observe a field-induced Chern gap with Chern number $C=-6$ emanating from charge neutrality; in this gap, the Hall resistance is quantized to within $2\%$ of the expected value, $-h/6e^2$, at 4.6 K. We explain this behavior using both Hofstadter and orbital Zeeman calculations, which show that a moderate magnetic field drives a valley-selective topological transition. Above the transition, the total Chern number of the occupied states in each spin-valley flavor becomes identical across neighboring domains, and the domain-wall modes can become gapped. Though the central valence-band Chern numbers still differ between the two domain types, the observed quantized transport attests to a global gap.

We establish the spectral foundation of the geometric formulation of Cooper pairing in the Yukawa–Sachdev–Ye–Kitaev model. Starting from the large-$N$ bilocal effective action, we derive the Gaussian fluctuation kernel in the even-frequency spin-singlet Cooper channel. Following the construction of Maldacena and Stanford, we determine the kernel eigenvalue $k\left(h\right)$ analytically for arbitrary conformal weight $h$ and resolve the pairing fluctuations into the continuous and discrete sectors of the associated de-Sitter space Laplacian. We show that the superconducting instability and the universal low-energy fluctuations near it reside entirely in the continuous scattering sector, while the discrete modes remain non-critical. Expanding the kernel about the lowest continuum mode yields a Klein–Gordon action on ${\rm dS}_2$, restricted to the continuous spectral subspace. This is precisely the subspace on which the inverse Radon transform to ${\rm AdS}_2$ is well defined. The projected bilocal Cooper-pair field can therefore be mapped onto a scalar matter field propagating in ${\rm AdS}_2$, without requiring any further spectral restriction on the bulk theory. Our results provide the missing microscopic justification for the projection implicit in earlier holographic formulations and clarify how a local bulk field emerges from the bilocal pairing theory.

We present the cumulative SOAR TESS Survey, based on HRCam speckle observations of 2,982 targets, and report 433 companion measurements obtained after Survey II. In a demographic sample of 1,199 dwarf primaries, we compare detected companions with secondary-to-primary mass ratios $q=M_2/M_1\geq0.4$ to a field-star population after accounting for each observation's detection limits. We find 24 companions within 50 au versus 84.8 expected and 48 within 100 au versus 124.4 expected. The companion frequencies relative to the field expectation are $S_{50\,{\rm au}}=0.291^{+0.062}_{-0.054}$ and $S_{100\,{\rm au}}=0.391^{+0.058}_{-0.053}$. A continuous model in which the deficit weakens with separation reaches the midpoint between close-binary suppression and the field rate at $a_{50}=74$ au (57–101 au). The Gaia-matched subset contains 88 companions versus 69.6 expected, a difference consistent with the model once uncertainties in the field comparison and Gaia selection are included. A model that preserves the total number of binaries but shifts the field distribution toward 100 au fits poorly. Under the limiting assumption that all retained planets orbit the catalog primary, the fitted law implies reductions of 17.0% in volume-limited planet yield over $q\geq0.4$ and 23.3% when extended to all mass ratios. M-dwarf hosts show a similar close-companion deficit, but the smaller sample prevents a precise comparison with solar-type hosts.

The pericentric distances of satellite galaxies govern their tidal stripping, quenching, and survival, yet their orbits are almost universally computed in spherical host haloes, whereas dark matter haloes are generically triaxial. We quantify, orbit by orbit, the error this simplification incurs. We integrate $10^6$ satellites, drawn from a cosmological infall distribution, in static NFW hosts of systematically varying triaxiality at fixed mass profile. Triaxiality leaves the population medians of pericentre, apocentre, and orbital period essentially unchanged. Instead, successive pericentres of an individual orbit scatter by 5-23% depending on host shape, irrespective of orbital energy; the minimum pericentre distance reached within a Hubble time shrinks systematically by up to 21%, enhancing the peak tidal mass loss. This triaxiality-driven orbital dephasing is overwhelmingly regular rather than chaotic; chaotic satellite orbits are common and dominate the near-centre pericentric passages in strongly flattened hosts, but diverge on time-scales far exceeding the Hubble time. Satellite orbits spherically reconstructed via direct backward integration in a truly triaxial host diverge by a tenth of the virial radius within 2-4 Gyr, with comparable uncertainties sourced separately by the unconstrained shape of the host and by its unknown absolute orientation. For the Milky Way dwarf Triangulum II, the unknown halo shape and orientation alone spread the inferred pericentre by ~50%, five times its reported uncertainty and more than ten times the LMC-induced shift, and bias it by 6-70%. This host-shape uncertainty can dominate satellite orbital error budgets and should be incorporated in future inferences.

We present FlaSR, a Mathematica package for the automatic generation of higher-order amplitude and amplitude-squared $SU(2)$ flavor sum rules, with a particular emphasis on $U$-spin. The package is based on recent insights into the mathematical structure of flavor sum rules. Given a system of symmetry-related processes defined by a list of particle multiplets in the initial and final states, together with the transformation properties of the symmetry-limit Hamiltonian, the package generates the full list of processes and outputs amplitude and amplitude-squared sum rules for the system. For amplitude sum rules, the package generates the complete set at all orders in symmetry breaking for which such relations exist. For amplitude-squared sum rules, which translate directly into sum rules among physical observables, the current version of the package is not guaranteed to generate the complete set. We illustrate the scope of the package with a range of representative examples.

Primordial black holes (PBHs) remain compelling dark-matter candidates and possible relics of early-Universe physics, with observable imprints across both cosmological structure formation and gravitational-wave astronomy. We investigate the consequences of a PBH population described by an extended, physically motivated mass function shaped by features in the thermal history of the early Universe. We compute the associated Poisson contribution to the matter power spectrum and propagate its effects to the halo mass function, the cosmic star-formation rate density, and the reionization history. The PBH component produces a moderate enhancement of small-scale power, leading to earlier low-mass halo formation and a correspondingly mild increase in the high-redshift star-formation rate density while remaining consistent with current constraints on the Thomson optical depth. We then evaluate the merger-rate distribution expected for current and future gravitational-wave detectors. In the stellar-mass regime, the predicted PBH binary population occupies the region probed by LIGO-Virgo-KAGRA and can contribute to the observed compact-object merger population. For LISA, the detectable signal is dominated by intermediate-mass binaries with component masses of $10^3$-$10^4\,M_\odot$, with cumulative rates of order a few events per year extending to redshifts as high as $z \sim 50$. The detection of such high-redshift intermediate-mass black hole mergers would constitute a distinctive signature of a primordial origin, providing evidence that PBHs contribute non-negligibly to the dark matter budget and may have served as early seeds for the supermassive black holes observed at later cosmic epochs.

Energy correlators are universal observables, well defined across a wide range of theories and spacetime dimensions, from gauge theory and conformal field theory to string theory. Energy correlators are constrained by three fundamental properties: pointwise positivity of the energy flux, global positivity originating from their interpretation as state norms in a unitary theory, and energy conservation organizing multi-point energy correlators into an infinite consistent hierarchy. We argue that the most general solution to the infinite hierarchy positivity problem of energy correlators is given by the event distribution formula, which expresses energy correlators as moments of the measure on the space of probability measures on the celestial sphere. We work out in detail implications of positivity for two- and three-point energy correlators and show that it implies nontrivial two-sided bounds on their multipole expansion coefficients. The bounds obtained by requiring consistency of the infinite hierarchy of energy correlators are strictly stronger than those obtained by imposing positivity of the two- and three-point correlators alone. For the low-spin multipole coefficients studied in the paper, the derived bounds are optimal in the sense that their extrema are realized by finite mixtures of finite-particle events. We further demonstrate consequences of positivity in energy correlators in collider physics and conformal field theories.

Pair-density waves (PDWs) are unconventional superconducting states beyond the BCS paradigm, but identifying them unambiguously in microscopic lattice models is generally challenging due to various competing orders. In particular, an exact realization of PDW in interacting models with topological bands remains elusive. Here we construct an interacting model on a twisted bilayer checkerboard lattice (TBCB) featuring topological flat bands, and rigorously show that an exact PDW ground state can be induced by quantum geometric nesting (QGN), owing to its momentum-space nonsymmorphic symmetry. We further prove that the superfluid stiffness of any nondegenerate QGN superconductor (including the PDW studied here and uniform superconductor) obeys the universal relation $D_s=2N_{\rm flat}\nu(1-\nu)m_{\rm pair}^{-1}$, where $N_{\rm flat}$, $\nu$, and $m_{\rm pair}$ are the number of flat bands, flat band filling, and the two-particle effective mass, respectively. Our results reveal a rich interplay among PDW order, quantum geometry, and band topology.

Motivated by inflation and Liouville theory, we consider random $d$-dimensional geometries characterized by an overall scale factor $ds^2 = e^{2 \zeta} dx^2 $ given in terms of a random Gaussian field $\zeta(x)$ with logarithmic correlations. We discuss aspects of the renormalization of the volume element $e^{d \zeta }$, connecting well-known Liouville theory formulas (KPZ) and inflationary ones. By starting from a fixed physical cutoff and coarse-graining operators to a fixed fiducial cutoff, defined via the flat metric $dx^2$, we provide a direct physical derivation of the KPZ scaling relation. We point out that the same renormalization problem arises in stochastic inflation, where it is modeled by Brownian motion of the inflaton field. We show that the breakdown of the renormalization of the Liouville volume when the fluctuation amplitude exceeds a critical value corresponds to the transition to eternal inflation. In $d = 2$, this matches the familiar $c_m = 1$ barrier in Liouville gravity. We also discuss connections to mathematical probabilistic approaches to random surfaces.

Mrk 590 is a changing-look AGN (CLAGN) that slowly faded from a Seyfert Type 1 to near quiescence over a few decades before re-igniting in 2017. Monitoring in the optical/UV/X-ray wavebands has revealed accretion-driven variability signatures, but the response of the radio source to the changing-look events that drove its fading and re-ignition is unknown. We present multi-frequency (1-17~GHz), A-configuration, Karl G. Jansky Very Large Array (VLA) observations of Mrk 590 over four epochs from 2015 to 2017. The radio source is dominated by a faint, compact component, absent of any notable extended structures. We identify a variable radio spectrum over this period, both in amplitude and in shape, and implement a Bayesian inference modeling routine to constrain the mechanism driving the radio variability. Our routine favors radio variability powered by a bow shock produced through an interaction of a radio jet with the interstellar medium, which drives the radio brightening in later epochs. This demonstrates that the radio variability we observed is not correlated with the variable accretion event that led to the re-brightening of the AGN at higher energy wavebands. While correlated variability between the radio and accretion-driven emission has been observed in other CLAGN, the lack of correlated variability in Mrk 590 shows the diversity of changing-look AGN populations and the mechanisms driving their behavior.